This invention relates to surgical instruments and particular to powered saws for the removal of orthopaedic bandages of the hard casting material type.
Portable cast cutters or saws have been known for many years and are formed having a small circular or part circular saw blade that oscillates through a limited angle to cut through a hard cast material such as plaster or a resinous material. The small angle oscillations, however, assure that the soft tissue of the patient wearing the cast will not be damaged. These oscillations are driven by a suitable transmission which may include various types of mechanical interconnections that are well known in the art. The transmission itself is normally driven by a small electric motor. During the cast removal operation there is a significant quantity of dust and debris generated by the operation. In order to remove this dust and debris it is known to connect the hose of a conventional vacuum cleaner to the saw itself. Such an arrangement is shown in U.S. Pat. No. 2,929,177. Other examples of fan-type dust and debris removal systems are shown in U.S. Pat. Nos. 3,103,069 and 3,481,036.
U.S. Pat. No. 4,421,111 discloses a low voltage surgical cast cutter with a vacuum exhaust of debris. This device is described as a surgical cast cutter or other power tool which contains a main tool section and a complimentary hose section releasably secured to the tool section at a rear end thereof. A low voltage electric motor in the tool section drives a transmission which oscillates a cutter mounted forwardly of the tool section. A debris conduit in the tool section communicates with an opening formed in the hose section when the sections are joined together. The hose section carries a flexible vacuum hose communicating with the opening therein, thereby facilitating removal of dust particles generated during operation of the cutter to remove, for example, a plaster cast. This device, however, is bulky and cumbersome to use as the vacuum attachment is separate from the cutter itself and rather large. This requires that a power pack or a vacuum source be attached to the device and positioned near the device.